In the Ordinary Form, today is the feast of Pope Saint Leo the Great.
Here you can see where he is buried in the Basilica of Saint Peter in Vatican City. You can usually see it, but it is harder to get up to the alter itself. For some reason, that area of the basilica is usually closed off, so the closest you can get is about 30 yards away. Your best bet to visit the altar is to got to Saint Peter's right when it opens in the morning and attend one of the low private Masses at this altar. I was blessed last year with the opportunity to do this, so I snapped a couple of pictures afterwards.
So, here's just one of the many Saint's buried in Saint Peter's.
I also encourage you read Pope Saint Leo the Great's homilies. They are often very clear and solid expositions of the Faith.
You've got to love a guy who stood up to Attila the Hun.